Even with a stronger economy, businesses face an uphill battle when it comes to making a profit.

Which is why it’s not surprising that much of a company’s success hinges on its employees. But what if an employee is fighting a medical condition or illness? How impactful is that to a business’s bottom line? It turns out: quite a lot.

Unlike absenteeism, according to a recent study, presenteeism – when people show up for work but don’t or can’t perform at full capacity – isn’t always apparent. You know when someone doesn’t show up for work, but you often can’t tell when – or how much – health problems, including chronic conditions such as back pain, headaches, and arthritis, can leave them muddling through the day.

“Underlying the research on presenteeism is the assumption that employees do not take their jobs lightly, that most of them need and want to continue working if they can,” the Harvard Business Review reports.

Many attribute the problem to the current opioid crisis, claiming that it’s in employers’ best interest to see that their workers have access to safer options to such potentially addictive (or worse) prescription painkillers such as OxyContin. One popular approach for relief from neuromusculoskeletal issues such as low-back and neck pain – drug-free chiropractic care – has actually been incorporated in on-site wellness programs by companies such as Google, Apple and Facebook.

Doctors of chiropractic, who are highly educated and trained in the structure and function of the human body, use hands-on techniques designed to enhance flexibility, muscle strength, and range of motion. Most insurance policies cover its use.

“Chiropractic care is a win-win situation for both businesses and their employees,” says the Foundation for Chiropractic Progress’s Sherry McAllister, DC.

So how much money does this phenomenon impact businesses’ bottom line? According to a new report by Global Corporate Challenge, presenteeism costs companies 10 times as much as the $150 billion annually in lost productivity from absenteeism.